rockchip: Pinebook Pro: enable rng to provide an entropy source

Enable the rng so UEFI can provide entropy for KASLR

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

arch/arm/dts/rk3399-pinebook-pro-u-boot.dtsi

@@ -24,6 +24,10 @@
 	u-boot,dm-pre-reloc;
 };
 
+&rng {
+	status = "okay";
+};
+
 &sdhci {
 	max-frequency = <25000000>;
 	u-boot,dm-pre-reloc;

arch/arm/dts/rk3399-rockpro64-u-boot.dtsi

@@ -19,6 +19,10 @@
 	};
 };
 
+&rng {
+	status = "okay";
+};
+
 &spi1 {
 	spi_flash: flash@0 {
 		u-boot,dm-pre-reloc;

configs/pinebook-pro-rk3399_defconfig

@@ -54,6 +54,8 @@ CONFIG_DM_PMIC_FAN53555=y
 CONFIG_PMIC_RK8XX=y
 CONFIG_REGULATOR_PWM=y
 CONFIG_REGULATOR_RK8XX=y
+CONFIG_DM_RNG=y
+CONFIG_RNG_ROCKCHIP=y
 CONFIG_PWM_ROCKCHIP=y
 CONFIG_RAM_RK3399_LPDDR4=y
 CONFIG_DM_RESET=y